Serial proton MR spectroscopy and diffusion tensor imaging in infantile Balo's concentric sclerosis

Knowledge and awareness on Balo's disease among dental students: A survey

Balo's disease is an uncommon central nervous system disorder causing demyelination and is a form of multiple sclerosis. Concentric sclerosis, leukoencephalitis periaxialis concentrica, is also known as Balo's disease. Concentric sclerosis signalizes the bands of intact myelin and alternating rings of myelin loss present in several parts of the brainstem and brain. The present study aimed to assess and create awareness about Balo's disease among dental undergraduates. The study included an online survey about the knowledge and awareness of Balo's disease among dental students. A questionnaire was prepared, uploaded, and distributed in an online portal. The latest software version of SPSS was used to analyze the collected data. Descriptive statistical analysis and Chi-square test were done, and the P value was calculated. The survey showed that 54.55% of males and 45.45% of females participated in this survey. Most of the respondents (87.88%) knew about Balo's disease, whereas only 12.12% of participants were not aware of the disease. It was found that most of dental students are aware of Balo's disease. The study also showed that male respondents are more aware than the females.

From Baló's concentric sclerosis to multiple sclerosis: a series of 6 patients

INTRODUCTION

Baló's concentric sclerosis (BCS) is a rare CNS disorder characterized by alternating bands of demyelination on MRI. One of the main issues is its relationship with multiple sclerosis (MS).

OBJECTIVES

To describe 6 BCS patients. To review the risk of developing MS in BCS patients.

METHODS

We retrospectively recorded clinical and radiological findings of 6 BCS patients and performed a review of the literature.

RESULTS

Six patients (5 women) with a mean age of 25 years old were included. Main symptoms were hemiparesis/hemihypoesthesia. On MRI, two patients had a single BCS lesion and four had additional MS-like lesions. Alternating bands were usually more visible on DWI. A patient had reduced central perfusion and SWI hypointensity suggestive of a central vein. Oligoclonal bands were identified in 5/6 patients. After 7 years of follow-up, all patients achieved MS criteria with mild disability (mean EDSS 1.75; 0-4). Our literature review included 65 BCS patients from 30 studies: although CSF oligoclonal bands and the presence of additional MS lesions were associated with subsequent relapses, this was not significant.

DISCUSSION/CONCLUSION

Our series allows a detailed MRI description in BCS and gives a new insight into BCS evolution and its strong relationship with MS.

Multifocal Balo's Concentric Sclerosis in Children: Report of a Case and Review of Literature

Balo's concentric sclerosis (BCS) is a rare demyelinating lesion considered to be a variant of multiple sclerosis (MS). On magnetic resonance imaging (MRI) Balo's concentric sclerosis shows the typical concentric pattern. We report a case of 10 year old child with BCS who presented as post infectious acute disseminated encephalomyelitis (ADEM). He is asymptomatic and had no relapse after 6 years of follow-up.

Balo’s concentric sclerosis in a patient with spontaneous remission based on magnetic resonance imaging: A case report and review of literature

Balo’s concentric sclerosis (BCS) is a rare monophasic demyelinating disease known as multiple sclerosis subtype and seen as a round lesion with variable hyper and hypo-detoxification layers. Characteristic appearance can be seen as “bulb eye” or “onion bulb”. The initial terminology for this neurological disorder was leukoencephalitis periaxialis concentrica; this is defined as a disease in which the white matter of the brain is destroyed in concentric layers in such a way as to leave the axial cylinders intact. This report presents a case of BCS with spontaneous healing of the patient and a mass lesion with concentric rings adjacent to the left lateral ventricle and the posterior portion of the corpus callosum with peripheral vasogenic edema. The neurological lesion of the patient was similar to the magnetic resonance imaging and clinical findings of the BCS.

Diagnostic and prognostic value of in vivo proton MR spectroscopy for Zellweger syndrome spectrum patients

Defects in the biogenesis of peroxisomes cause a clinically and genetically heterogeneous group of neurometabolic disorders, the Zellweger syndrome spectrum (ZSS). Diagnosis predominantly is based on characteristic clinical symptoms, a typical biochemical profile, as well as on identification of the molecular defect in any of the 12 known human PEX genes. The diagnostic workup can be hindered if the typical clinical symptoms are missing and predicting the clinical course of a given patient is almost unfeasible. As a safe and noninvasive method to analyze specific chemical compounds in localized brain regions, in vivo proton magnetic resonance spectroscopy (MRS) can provide an indication in this diagnostic process and may help predict the clinical course. However, to date, there are very few reports on this topic. In this study, we performed localized in vivo proton MRS without confounding contributions from T1- and T2-relaxation effects at 2 Tesla in a comparably large group of seven ZSS patients. Patients' absolute metabolite concentrations in cortical gray matter, white matter, and basal ganglia were assessed and compared with age-matched control values. Our results confirm and extend knowledge about in vivo MRS findings in ZSS patients. Besides affirmation of nonspecific reduction of N-acetylaspartate + N-acetylaspartylglutamate (tNAA) in combination with lipid accumulation as a diagnostic hint for this disease group, the amount of tNAA loss seems to reflect disease burden and may prove to be of prognostic value regarding the clinical course of an already diagnosed patient.

Single-shot T1 mapping of the corpus callosum: a rapid characterization of fiber bundle anatomy

Using diffusion-tensor magnetic resonance imaging and fiber tractography the topographic organization of the human corpus callosum (CC) has been described to comprise five segments with fibers projecting into prefrontal (I), premotor and supplementary motor (II), primary motor (III), and primary sensory areas (IV), as well as into parietal, temporal, and occipital cortical areas (V). In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area) from densely packed smaller axonal bundles (genu) with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

Balo concentric sclerosis in children: a case series

Baló concentric sclerosis is a unique and rare phenomenon in demyelinating disease. Typically thought of as a subtype of multiple sclerosis, Baló concentric sclerosis is characterized pathologically by striking rings of demyelination alternating with areas of preserved myelination. Its exact prevalence in adult and especially pediatric populations is unknown. Although traditionally considered to be an acute and fatal disease of adults, there are a handful of reports of Baló concentric sclerosis cases in pediatric patients. Here we report Baló concentric sclerosis-like demyelinating disease in 3 female pediatric patients, representing 2.2% of a cohort of 134 pediatric patients with demyelinating diseases who have been seen in our center since 2005. The relatively high prevalence of Baló concentric sclerosis-like cases in our pediatric demyelinating diseases center, none of which have been fatal, supports the premise that the developing immune and central nervous systems may manifest and respond to demyelinating disease differently from adults.

A Novel SLC6A8 Mutation in a Large Family with X-Linked Intellectual Disability: Clinical and Proton Magnetic Resonance Spectroscopy Data of Both Hemizygous Males and Heterozygous Females

X-linked creatine transport (CRTR) deficiency, caused by mutations in the SLC6A8 gene, leads to intellectual disability, speech delay, epilepsy, and autistic behavior in hemizygous males. Additional diagnostic features are depleted brain creatine levels and increased creatine/creatinine ratio (cr/crn) in urine. In heterozygous females the phenotype is highly variable and diagnostic hallmarks might be inconclusive. This survey aims to explore the intrafamilial variability of clinical and brain proton Magnetic Resonance Spectroscopy (MRS) findings in males and females with CRTR deficiency. X-chromosome exome sequencing identified a novel missense mutation in the SLC6A8 gene (p.G351R) in a large family with X-linked intellectual disability. Detailed clinical investigations including neuropsychological assessment, measurement of in vivo brain creatine concentrations using quantitative MRS, and analyses of creatine metabolites in urine were performed in five clinically affected family members including three heterozygous females and one hemizygous male confirming the diagnosis of CRTR deficiency. The severe phenotype of the hemizygous male was accompanied by most distinct aberrations of brain creatine concentrations (-83% in gray and -79% in white matter of age-matched normal controls) and urinary creatine/creatinine ratio. In contrast, the heterozygous females showed varying albeit generally milder phenotypes with less severe brain creatine (-50% to -33% in gray and -45% to none in white matter) and biochemical urine abnormalities. An intrafamilial correlation between female phenotype, brain creatine depletion, and urinary creatine abnormalities was observed. The combination of powerful new technologies like exome-next-generation sequencing with thorough systematic evaluation of patients will further expand the clinical spectrum of neurometabolic diseases.

Atypical idiopathic inflammatory demyelinating lesions (IIDL): conventional and diffusion-weighted MR imaging (DWI) findings in 42 cases

INTRODUCTION

The purpose of this study was to evaluate MR imaging characteristics with conventional and advanced MR imaging techniques in patients with IIDL.

METHODS

MR images of the brain in 42 patients (20 male, 22 female) with suspected or known multiple sclerosis (MS) from four institutions were retrospectively analyzed. Lesions were classified into five different subtypes: (1) ring-like lesions; (2) Balo-like lesions; (3) diffuse infiltrating lesions; (4) megacystic lesions; and (5) unclassified lesions. The location, size, margins, and signal intensities on T1WI, T2WI, and diffusion-weighted images (DWI), and the ADC values/ratios for all lesions, as well as the contrast enhancement pattern, and the presence of edema, were recorded.

RESULTS

There were 30 ring-like, 10 Balo-like, 3 megacystic-like and 16 diffuse infiltrating-like lesions were detected. Three lesions were categorized as unclassified lesions. Of the 30 ring-like lesions, 23 were hypointense centrally with a hyperintense rim. The mean ADC, measured centrally, was 1.50 ± 0.41 × 10(-3) mm(2)/s. The mean ADC in the non-enhancing layers of the Balo-like lesions was 2.29 ± 0.17 × 10(-3) mm(2)/s, and the mean ADC in enhancing layers was 1.03 ± 0.30 × 10(-3) mm(2)/s. Megacystic lesions had a mean ADC of 2.14 ± 0.26 × 10(-3)mm(2)/s. Peripheral strong enhancement with high signal on DWI was present in all diffuse infiltrating lesions. Unclassified lesions showed a mean ADC of 1.43 ± 0.13 mm(2)/s.

CONCLUSION

Restriction of diffusion will be seen in the outer layers of active inflammation/demyelination in Balo-like lesions, in the enhancing part of ring-like lesions, and at the periphery of infiltrative-type lesions.

Akinetic mutism caused by HIV-associated progressive multifocal leukoencephalopathy was successfully treated with mefloquine: a serial multimodal MRI Study

We report a case of a patient with highly active anti-retroviral therapy-resistant human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML). The patient showed an improvement in imaging findings and clinical symptoms after mefloquine was introduced as an additional treatment. Serial assessment of white matter lesions was conducted by proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion-weighted imaging (DWI). As the clinical symptoms improved, the N-acetylaspartate/creatine ratio increased, the choline/creatine ratio decreased, and the elevated ADC value decreased. These concomitant changes suggested that (1)H-MRS and DWI were useful for the assessment of the therapeutic effect on PML.

Advanced magnetic resonance imaging techniques in the evaluation of pediatric white matter diseases

This article aimed to describe the technical principles and clinical application of advanced magnetic resonance imaging techniques for the assessment of white matter diseases. The following techniques are going to be discussed: magnetization transfer, proton magnetic resonance spectroscopy, diffusion-weighted imaging, diffusion tensor imaging, as well as perfusion and postprocessing techniques such as tract-based spatial statistics. These techniques allow a better understanding of the physiopathology of the white matter diseases as well as have a significant impact on the definition of the differential diagnosis and treatment options.

In vivo proton MR spectroscopy findings specific for adenylosuccinate lyase deficiency

Adenylosuccinate lyase (ADSL) deficiency is an inherited metabolic disorder affecting predominantly the central nervous system. The disease is characterized by the accumulation of succinylaminoimidazolecarboxamide riboside and succinyladenosine (S-Ado) in tissue and body fluids. Three children presented with muscular hypotonia, psychomotor delay, behavioral abnormalities, and white matter changes on brain MRI. Two of them were affected by seizures. Screening for inborn errors of metabolism including in vitro high resolution proton MRS revealed an ADSL deficiency that was confirmed genetically in all cases. All patients were studied by in vivo proton MRS. In vitro high resolution proton MRS of patient cerebrospinal fluid showed singlet resonances at 8.27 and 8.29 ppm that correspond to accumulated S-Ado. In vivo proton MRS measurements also revealed a prominent signal at 8.3 ppm in gray and white matter brain regions of all patients. The resonance was undetectable in healthy human brain. In vivo proton MRS provides a conclusive finding in ADSL deficiency and represents a reliable noninvasive diagnostic tool for this neurometabolic disorder.

High field MRI in the diagnosis of multiple sclerosis: high field-high yield?

Following the approval of the U.S. Food and Drug Administration (FDA), high field magnetic resonance imaging (MRI) has been increasingly incorporated into the clinical setting. Especially in the field of neuroimaging, the number of high field MRI applications has been increased dramatically. Taking advantage on increased signal-to-noise ratio (SNR) and chemical shift, higher magnetic field strengths offer new perspectives particularly in brain imaging and also challenges in terms of several technical and physical consequences. Over the past few years, many applications of high field MRI in patients with suspected and definite multiple sclerosis (MS) have been reported including conventional and quantitative MRI methods. Conventional pulse sequences at 3 T offers higher lesion detection rates when compared to 1.5 T, particularly in anatomic regions which are important for the diagnosis of patients with MS. MR spectroscopy at 3 T is characterized by an improved spectral resolution due to increased chemical shift allowing a better quantification of metabolites. It detects significant axonal damage already in patients presenting with clinically isolated syndromes and can quantify metabolites of special interest such as glutamate which is technically difficult to quantify at lower field strengths. Furthermore, the higher susceptibility and SNR offer advantages in the field of functional MRI and diffusion tensor imaging. The recently introduced new generation of ultra-high field systems beyond 3 T allows scanning in submillimeter resolution and gives new insights into in vivo MS pathology on MRI. The objectives of this article are to review the current knowledge and level of evidence concerning the application of high field MRI in MS and to give some ideas of research perspectives in the future.